/**
 * Copyright (c) 2007-2008 Nearchos Paspallis
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

/**
 * AspectSense
 *
 * Middleware for annotation-based, context-aware and adaptive services for
 * mobile and ubiquitous computing
 *
 * This project is an open-source effort, initiated by Nearchos Paspallis as
 * part of his PhD work at the University of Cyprus (http://www.ucy.ac.cy).
 *
 * More information about the project is available at "http://aspectsense.org".
 */

package org.aspectsense.framework;

import java.util.Map;
import java.util.HashMap;
import java.util.Set;

/**
 * @author Nearchos Paspallis [nearchos@cs.ucy.ac.cy]
*         Date: Jan 28, 2008
*         Time: 11:44:17 AM
*/
class ServiceProvidersUtility
{
    private final String serviceID;

    /**
     * Maps {@link org.aspectsense.framework.Component} IDs (corresponding to service provider) to
     * double values (utilities). When (if) multiple services are offered
     * per component, then the utility corresponds to that of the specified
     * {@link org.aspectsense.framework.Service} ID.
     */
    private final Map<String, Double> providerUtility
            = new HashMap<String, Double>();

    ServiceProvidersUtility(final String serviceID)
    {
        this.serviceID = serviceID;
    }

    Double putServiceProviderUtility(final String componentID, final Double utility)
    {
        return providerUtility.put(componentID, utility);
    }

    Set<String> getAllProviders()
    {
        return providerUtility.keySet();
    }

    double getUtility(final String componentID)
    {
        return providerUtility.get(componentID);
    }

    String getComponentWithMaxUtility()
    {
        // todo optimize
        double optimalUtility = -1;
        String optimalComponentID = null;

        final Set<String> componentProviderIDs = providerUtility.keySet();
        for(final String componentProviderID : componentProviderIDs)
        {
            double providedUtility = providerUtility.get(componentProviderID);
            if(providedUtility > optimalUtility)
            {
                optimalUtility = providedUtility;
                optimalComponentID = componentProviderID;
            }
        }

        return optimalComponentID;
    }

    String getServiceID()
    {
        return serviceID;
    }

    /**
     * This method is overloaded for debugging purposes. It returns a string
     * representing the current object's state.
     *
     * @return a string representing the current object's state.
     */
    public String toString()
    {
        final StringBuilder stringBuilder = new StringBuilder();

        stringBuilder.append(serviceID).append(" ::= ");
        final Set<String> providers = providerUtility.keySet();
        for(final String provider : providers)
        {
            stringBuilder.append(provider).append("->").append(providerUtility.get(provider)).append(" | ");
        }

        return stringBuilder.toString();
    }
}
